Fritz Mellert

Dr. Fritz Mellert


Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 December 2024 in Journal of Clinical Medicine
Verified
Journal Article
Open access
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MSMathieu Suleiman
Mathieu Suleiman
Abbas AgaimyAbbas Agaimy
Abbas Agaimy
ODOliver Dewald
Oliver Dewald
AKAnn-Sophie Kaemmerer-Suleiman
Ann-Sophie Kaemmerer-Suleiman
FMFritz Mellert
Fritz Mellert
FHFrank Harig
Frank Harig
Background: Calcified amorphous tumor (CAT) is a rare, mostly incidental tumor-like cardiac lesion of unknown histogenesis. Current imaging modalities do not differentiate between CAT and other masses. As it can be a source for embolization, surgical excision of CAT is mandatory. CAT in patients with Granulomatosis with polyangiitis (GPA) is exceedingly rare. Methods: This systematic literature review was prompted by the case of a CAT in a patient with GPA. The search of all types of studies in two databases (PubMed and Scopus) was conducted through November 2024 to identify the relevant studies. Results: Nine studies were included describing cases of patients being diagnosed with GPA and a cardiac mass. All included patients had a histopathological examination of the either biopsied or surgically resected mass. Only one case reported a CAT. In our case, the patient was diagnosed with GPA through a kidney biopsy, whereas a cardiac mass in the right atrium was diagnosed by echocardiography during evaluation for possible kidney transplantation. One year later a progression was observed, and the mass was resected. The histopathological examination revealed a CAT. The patient could be successfully discharged in a good clinical condition. Conclusions: This systematic literature search and case report highlight the importance of regular echocardiographic examination in patients with GPA. Moreover, surgical excision is crucial for the diagnosis and for further therapy planning, regardless of whether the mass is neoplastic or not.

Verified
Journal Article
Open access
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RPRobert David Pittrow
Robert David Pittrow
HDHarald Kaemmerer, Dr. Dr.
Harald Kaemmerer, Dr. Dr.
AFAnnika Freiberger
Annika Freiberger
SAStefan Achenbach
Stefan Achenbach
GBGert Bischoff
Gert Bischoff
MSMathieu Suleiman
Mathieu Suleiman
Background: The PATHFINDER-CHD Registry is a prospective, multicenter, non-interventional registry across tertiary care centers in Germany. The aim is to analyze real-world data on adults with congenital heart defects (ACHD) or hereditary connective tissue disorders who have manifest heart failure (HF), a history of HF, or are at significant risk of developing HF. This analysis investigates the prevalence and clinical impact of overweight and obesity in this unique population. Methods: As of 1st February, 2025, a total of 1490 ACHD had been enrolled. The mean age was 39.4 ± 12.4 years, and 47.9% were female. Patients were categorized according to Perloff’s functional class and the Munich Heart Failure Classification for Congenital Heart Disease (MUC-HF-Class). Results: The most common congenital heart disease (CHD) in this cohort was Tetralogy of Fallot, transposition of the great arteries, and congenital aortic valve disease. Marfan syndrome was the most common hereditary connective tissue disease. Of the patients, 46.1% were classified as overweight (32.8%) or obese (13.3%), while 4.8% were underweight. The highest prevalence of overweight (47.1%) was observed among patients who had undergone palliative surgery, whereas untreated patients showed the highest proportion of normal weight (57.2%). Cyanotic patients were predominantly of normal weight. Patients with univentricular circulation exhibited significantly lower rates of overweight and obesity (35%; p = 0.001). Overweight and obesity were statistically significantly associated with arterial hypertension, diabetes mellitus, and sleep apnea (all p < 0.001). High BMI was linked to increased use of HF-specific medications, including SGLT2 inhibitors (p = 0.040), diuretics (p = 0.014), and angiotensin receptor blockers (p = 0.005). Conclusions: The data highlight the clinical relevance of overweight and obesity in ACHD with HF, emphasizing the need for individualized prevention and treatment strategies. The registry serves as a critical foundation for the optimization of long-term care in this population.

20 November 2025 in Geriatrics
Verified
Journal Article
Open access
PDF file
AKAnn-Sophie Kaemmerer-Suleiman
Ann-Sophie Kaemmerer-Suleiman
FHFrank Harig
Frank Harig
AFAnnika Freiberger
Annika Freiberger
ODOliver Dewald
Oliver Dewald
SAStephan Achenbach
Stephan Achenbach
FMFritz Mellert
Fritz Mellert
Background: Advances in diagnosis and treatment have led to a growing population of adults with congenital heart disease (ACHD). Despite increasing life expectancy, their clinical needs—especially in older age—remain poorly defined. Cardiac and non-cardiac comorbidities are prevalent, and emerging evidence suggests accelerated biological aging compared to the general population. However, data on older patients and geriatric patients with CHD are limited. Objectives: This study aimed to characterize patients with CHD aged ≥50 years, focusing on functional status, comorbidities, sex-specific differences, and therapeutic patterns. Methods: The PATHFINDER-CHD Registry is a prospective, observational, multicenter registry enrolling patients with CHD with manifest heart failure (HF), HF history, or high HF risk. Data include anatomy, prior treatments, comorbidities, and medication use. Results: Among 1935 patients, 297 were ≥50 years old. Most had acyanotic CHD (62%); Tetralogy of Fallot (21%) was the most frequent diagnosis. A morphologic right systemic ventricle was present in 12%, and 5% had univentricular hearts. HF was manifest in 21%; 44% were classified as ACC/AHA stage B, 51% as stage C, yet 77% were in Perloff class I/II. Common cardiovascular comorbidities included aortopathy (55%), hypertension (37%), and arrhythmia (33%). Non-cardiac comorbidities included thyroid dysfunction (25%), renal impairment (18%), and neurological disease (13%). Sex-specific differences were observed. Despite HF burden, SGLT2 inhibitors and ARNIs were used in only 17% and 8.4%, respectively. Conclusions: Older patients with CHD represent a clinically complex cohort with high comorbidity burden. The findings support the concept of accelerated aging and emphasize the need for tailored interdisciplinary care strategies.

Verified
Journal Article
Open access
PDF file
AKAnn-Sophie Kaemmerer-Suleiman
Ann-Sophie Kaemmerer-Suleiman
SFSebastian Freilinger
Sebastian Freilinger
AFAnnika Freiberger
Annika Freiberger
ODOliver Dewald
Oliver Dewald
SAStefan Achenbach
Stefan Achenbach
FMFritz Mellert
Fritz Mellert
Background/Objectives: Heart failure (HF) poses a major challenge in managing adults with congenital heart defects (ACHD). Emerging evidence suggests that HF in ACHD increases the risk of underweight due to heightened metabolic demands, gastrointestinal complications, and psychological factors such as anxiety and depression. Despite its critical implications, few studies have examined this association. This study evaluates the relationship between HF and underweight—defined as a body mass index (BMI) < 18.5—in ACHD. Methods: The Pathfinder-CHD Registry is a prospective, observational, web-based HF registry including ACHD with manifest HF, history of HF, or significant risk for HF. It documents congenital diagnoses, HF type, comorbidities, and treatments. Patients were categorized by BMI into mild (17.00–18.49), moderate (16.00–16.99), and severe (<16.00) underweight. Results: As of September 2024, the registry enrolled 1420 adults (mean age 31.8±11.3 years; 49.2% female). Underweight was present in 59 patients (4.2%): 62.7% mild, 18.6% moderate, and 18.6% severe. Among the remaining 1361 patients, 52.8% had normal weight, 32.8% were overweight, and 14.2% were obese. Women had significantly lower metabolic body weight than men (p = 0.002). Underweight correlated with younger age (p < 0.001) and CHD type (p = 0.02). Notably, 42.9% of underweight patients had cyanotic CHD. Conclusions: Underweight is an underrecognized problem in ACHD with HF. Adults with complex CHD or connective tissue disorders are disproportionately affected. Underweight should be seen as an alarm sign requiring personalized, multidisciplinary management, including nutritional support, tailored therapy, and close monitoring to improve outcomes.